CONCRETIONS IN LAKE DEPOSITS 

 AT ELYRIA, OHIO 



GEORGE D. HUBBARD 

 Department of Geology, Oberlin College 



Excavations near the corner of Middle Avenue and Sixth 

 Street, Elyria, made preparatory to the erection of heating 

 plant extensions for the school buildings located there, have 

 brought to light some calcareous sand and clay concretions in 

 the making. 



The pit is twelve or fourteen feet in depth. The section is 

 as follows: 



4. Filling, artificial, (clay, brick-bats, crockery, etc.), 2 ft. 



3. Brown to yellow sands and clays 8 ft. 



2. Blue and blue-gray clays 2 ft. 



1. Blue sands 1-2 ft. 



Layer number one is micaceous sand and in parts argilla- 

 ceous. It gives under the weight of horses and wagon and 

 behaves much like quicksands. It seems to be full of water, 

 but the water is not flowing through. Layer number two is 

 dryer and is variable in thickness, the upper surface being 

 quite uneven. In places the layers above seem to be pushed 

 into it. In other parts a yellow stain seems to have penetrated 

 the blue clays from some point or line of seepage, in concentric 

 spheres or layers. Thus the yellow above and the blue below 

 are mutually interpenetrating and uneven. It is along this 

 uneven contact that the concretions occur. The circulating 

 water responsible for the concretions seems to be moving 

 through layer three and descending to number two. 



Some of the concretions are small and of indefinite bound- 

 aries and shapes, some are larger and resemble in shape lemons, 

 cocoanuts and even vases a foot high, with a diameter of three 

 or four inches. Most concretions have a nucleus of some sort. 

 In many of these there seems to be a twig or branch of wood, a 

 quarter of an inch to an inch in diameter, which reaches the 

 whole length of the structure. In most cases, this twig retains 

 some of its woody structure and fiber. The clay and sand 



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